20 8. V. Wood,jun. — American and British Surface- Geology. 



period of minor glaciation appears to be that which we are now con- 

 sidering, and the only divergence between the opinion to which Mr. 

 Ward appears to have been led from a study of this district and 

 that to which I have been led by a study of the East and South of 

 England, consists in the submergence which he regards as having 

 followed the first and principal glaciation, and preceded the minor 

 one ; my view being that the first glaciation and the submergence 

 were coincident, and that the sea merely took the place of so much 

 of the ice as was below its level, as this wasted away before amelio- 

 ration of climate. 



In reference to this divergence of opinion I would observe that 

 the features displayed by the Lower Glacial series of beds in Cromer 

 Cliff present, as it seems to me, the clearest evidence of the increase 

 of submergence having taken place coincidently with the increase of 

 glacial conditions on the Eastern side of England up to that stage 

 in the Glacial period to which the Lower Glacial series of deposits 

 carry us — a part of the geological record, be it remembered, which 

 has been erased from any other part of Britain that may once have 

 furnished it, but which carries us onwards from the latest Crag 

 deposits with no more than an insignificant break. 



If, therefore, the glaciation came on in the North-west of England 

 without submergence, and its disappearance there was followed by 

 this submergence, it follows that a complete oscillation must have 

 occurred between the two sides of England, so that when the East 

 and South-east of England was rising, as it was during the later part 

 of the Upper Glacial formation and earlier part of the post-Glacial, 

 the west and north-west must have been going down ; but the red 

 and white chalk, derived from the Lincolnshire glacier, which 

 generated the chalky portion of the Upper Glacial, having got into 

 the gravel at nearly 500 feet elevation so far west as the old strait 

 between Ebrington Hill and the main island of the Cotteswolds, 

 seems strong evidence that the submergence of the west side of 

 England was to this height at least contemporaneous with that 

 of the East, when this glacier terminated in the sea in the way de- 

 scribed in a previous part of this paper. On the other hand, it 

 must be admitted that the character of the marine mollusca from 

 the beds of the Severn Valley is so much more recent and 

 British than is that of the mollusca of the East Anglian beds, even 

 up to the horizon of Bridlington and Dimlington, that they can 

 scarcely be synchronous. This objection, however, applies equally 

 to the Mollusca of the Lower Boulder-clay of Lancashire, and to 

 that found in the Glacial clay of Yorkshire north of the Wold-scarp, 

 while the gravels of the South-west which contain the Lincolnshire 

 debris have not yielded any molluscan remains. It is not unlikely, 

 therefore, that after the elevation which followed the Contorted 

 Drift of Cromer, there set in coincidently with the further emergence 

 of East Anglia an increase of the submergence northwards and 

 westwards, and that this accompanied, and perhaps caused, the retreat 

 of the ice from East Anglia, while the North and North-west re- 

 mained enveloped by it. The giving place by the Holderness 



